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head-space-solid-phase-microextraction
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Synthesis, Characterization and Implementation of 3D Nanoscale Epoxy–Polyhedral Oligomeric Silsesquioxanes Network for Isolation of Polycyclic Aromatic Hydrocarbons in Tea and Coffee
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
Polyhedral oligomeric silsesquioxanes (POSSs) are 3D nanoscale structures with fascinating potential to be used as extractive phases in solid phase microextraction (SPME). Here, as a case study, the octaglycidyldimethylsilyl polyhedral oligomeric silsesquioxane (POSS–epoxy) network was fabricated on a stainless steel wire via sol–gel methodology and used as a SPME fiber coating. The uniform pore structure, high surface area, and hydrophobicity of POSS–epoxy, make it susceptible toward isolation of non– to semi–polar compounds. Performance of the POSS–epoxy fiber coating was examined considering three classes of typical environmental pollutants including chlorobenzenes (CBs), benzene...
A highly thermal-resistant electrospun-based polyetherimide nanofibers coating for solid-phase microextraction Microextraction Techniques
, Article Analytical and Bioanalytical Chemistry ; Vol. 406, issue. 8 , March , 2014 , p. 2141-2149 ; Akbarinejad, A ; Aghakhani, A ; Sharif University of Technology
Abstract
A high-temperature-resisant solid-phase microextraction (SPME) fiber was prepared based on polyetherimide (PEI) by the electrospinning method. The PEI polymeric solution was converted to nanofibers using high voltages and directly coated on a stainless steel SPME needle. The scanning electron microscopy images of PEI coating showed fibers with diameter range of 500-650 nm with a homogeneous and smooth surface morphology. The SPME nanofibers coating was optimized for PEI percentage, electrospinning voltage, and time. The extraction efficiency of the coating was investigated for headspace SPME of some environmentally important polycyclic aromatic hydrocarbons from aqueous samples followed by...
Electrospun polyamide-polyethylene glycol nanofibers for headspace solid-phase microextration
, Article Journal of Separation Science ; Vol. 37, issue. 14 , 2014 , pp. 1880-1886 ; ISSN: 16159306 ; Najarzadekan, H ; Roostaie, A ; Sharif University of Technology
Abstract
A solution of polyamide (PA) containing polyethylene glycol (PEG) as a side low-molecular-weight polymer was electrospun. After synthesizing the PA-PEG nanofibers, the constituent was subsequently removed (modified PA) and confirmed by Fourier transform infrared spectroscopy. The scanning electron microscopy images showed an average diameter of 640 and 148 nm for PA and PA-PEG coatings, respectively, while the latter coating structure was more homogeneous and porous. The extraction efficiencies of PA, PA-PEG, and the modified PA fiber coatings were assayed by headspace solid-phase microextraction of a number of chlorophenols from real water samples followed by their determination by gas...
A metal organic framework-polyaniline nanocomposite as a fiber coating for solid phase microextraction
, Article Journal of Chromatography A ; Volume 1431 , 2016 , Pages 27-35 ; 00219673 (ISSN) ; Javanmardi, H ; Abbasi, A ; Banihashemi, S ; Sharif University of Technology
Elsevier B. V
Abstract
A metal organic framework-polyaniline (MOF/PANI) nanocomposite was electrodeposited on a stainless steel wire and used as a solid phase microextraction (SPME) fiber coating. The electropolymerization process was carried out under a constant deposition potential and applied to the corresponding aqueous electrolyte containing aniline and MOF particles. The employment of MOFs with their large and small cages and 3-D structures in synthesizing a nanocomposite was assumed to be efficient constitutes to induce more non-smooth and porous structures, approved by scanning electron microscopy (SEM) images. Three different MOFs were incorporated to synthesize the desired nanocomposites and the...